In communication systems that transmit over radio links, the radio link may be unexpectedly broken and the communication interrupted. The interruption can occur for a variety of reasons such as loss of synchronization between the communicating parties, increased attenuation of the signals, fading caused loss of signal of sufficient duration or equipment failure.
Prior art systems attempt to re-initiate communications by assuming that the prior communication channel remains available. The disadvantages to these systems is that it is desirable to reassign the prior communication channel to other users. Furthermore, there is no provision in these systems to deal with re-establishment of a communication when there is relative movement between the communicating parties.
Thus what is needed is a means and method to re-establish a communication link that takes into consideration relative movement of two communicating parties. What is also needed is a method of call re-establishment that is applicable for recovering from interruptions caused by other effects such as signal attenuation. What is also needed is a method for call re-establishment that recognizes when further attempts to re-establish a call are likely to be futile and releases any resources being held in support of the call.